Why 100% oil-free air is critical in jet engine testing

Airline transportation is held to the highest standards for safety, reliability, efficiency and environmental factors and the appropriate compressed air utilized for jet engine developmental testing is no different. 

24 Август 2017

When a jet engine manufacturer is developing a new engine, there is extensive testing that is conducted for years before it is allowed to be brought to market. During the developmental period, there are several critical tests that are done on the engine to prove that it meets the manufacturer’s design criteria and that it is also compliant to industry standards and regulations.

Some of these tests involve the ingestion of materials that would be present in airline flight conditions, such as water, hail, snow, ice, dust, sand and debris.  In order to perform successful ingestion process testing on the ground, they need to simulate the conditions that would be present at flying altitudes. Compressed air is needed as the energy source that propels testing materials into the engine as encountered in flights.  Not just any source of compressed air is adequate or acceptable for this application and it also usually requires several thousand cubic feet per minute with significant flow volume.

With so many delicate test probes and critical forms of instrumentation utilized, engine manufacturers pay close attention to air quality. 100% oil-free compressed air is the standard utilized in the industry for a variety of reasons.

The most obvious reason is because there is no oil present during inflight atmospheric conditions, so oil-lubricated air compressors are just not suitable for these tests. Also, traces of oil within the compressed air stream could produce inaccurate testing data.

There is no time for error or setbacks from poor data collection, so it is important to eliminate the risk of contamination by using 100% oil-free air.

Another important factor that is considered is when materials are sent through the engine and expelled out the back into the atmosphere. Testing grounds are usually large open field areas due to the large volumes of compressed air used for testing. If there are traces of oil in the air stream, it could create a risk of environmental contamination.

Air compressors either use oil-free technology or oil-lubricated technology, there is no in between. Names like “instrument quality” and “technically oil-free” sound appealing and make consumers think there is no oil carryover, but it is not true. There are ways to determine if an air compressor is truly oil-free. For more information on this, check out our blog post “Why should I use true Oil-free air”

Why 100% oil-free air is critical in jet engine testing

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